There is no need to re-adjust the Unichip unless the engine has been modified.

It is nearly impossible for the Unichip data to change after the Unichip ECU has been programmed, causing the engine to be detuned.

It is possible however for the fuel pressure to drop (if the fuel pump deteriorates) which would cause the engine to run a leaner air fuel ratio than normal.

Other items such as fuel injectors and spark plugs will need servicing from time to time which will also change the state of engine tune.

Your engine should always be tuned using the fuel, which you intend to use day to day.

Leaded fuel will always produce the best power result, as it will allow the engine to use all of the ignition timing in the timing map.

As most modern EFI engines utilise knock sensors, should you change from Leaded to unleaded, the engine’s knock sensors will detect detonation and reduce timing accordingly, resulting in a loss of power.

The Unichip ECU is usually fitted next to the factory engine control unit.

The Unichip ECU is marginally larger that a cigarette pack. Dimensions are 160mm length x 80mm height x 20mm width.

This depends on the engine configuration and whether the engine is standard or modified, normally aspirated or turbocharged, two or four wheel drive.

A vehicle that is factory standard normally aspirated two-wheel drive, can be completed in 3 hours.

A more sophisticated vehicle such as a 993 Twin Turbo Porsche may take up to 6 hours due to the extra mapping of turbocharger pressure.

Removing the Unichip is a simple 15 to 30 minute procedure.

Once the Unichip is removed, the factory engine control unit is returned to standard condition.

It is possible that the Unichip will be suitable for your next car, albeit appropriately reprogrammed.

There are four popular variants of Unichip hardware.